Wireless communication services for mobile vehicles, such as navigation and roadside assistance, have increased rapidly in recent years. Most of the available services apply to a motor vehicle in operation, but more recently, the demands and potential for services to a turned-off vehicle have grown. Services requested while the vehicle is off or in a quiescent mode include maintenance and diagnostic functions, system updates, vehicle position determination, unlocking of the doors, or vehicle alarm setting and silencing.
Normally when the mobile vehicle equipped with a telematics unit or vehicle communication device is turned off, equipment is placed into a powered-down or sleep mode. This sleep or discontinuous-receive mode includes, for example, a time when the vehicle communication device is scheduled to awaken and the duration for the vehicle communication device to be awake. The discontinuous-receive mode includes storing information such as time and vehicle location at the initiation of the sleep mode. The discontinuous-receive mode includes setting a time for the next wakening period, and a duration for the next service-ready mode. The discontinuous-receive mode also includes actions to place other systems in the mobile vehicle into a quiescent or powered-down mode, including for example the vehicle communications device, the telematics unit, or both. While powered down, the vehicle communication device checks an on-board clock or timer to determine when it is time to awaken.
A communication device and a telematics unit are placed into a powered-down mode for minimal power drain on the battery. To perform a requested function while the ignition is off, the vehicle is awakened, the desired function performed, and the vehicle placed back into the sleep mode.
One method currently in use is to synchronize the wake-up time with an incoming call from a telematics or service call center. When the vehicle is awakened, a call is received and responded to appropriately. The time period between wake-up operations varies from ten minutes, to several days or more if the vehicle has not been moved or driven for a while. To coordinate the wake-up function with the call from the call center, time at the call center and at the mobile vehicle needs to be synchronized. A global positioning system (GPS) unit in the mobile vehicle provides an accurate reading of time. After the call is received and the vehicle responds, the vehicle is put back into the sleep mode again after a predetermined duration, minimizing battery drain.
Unfortunately, a prescribed wake-up schedule will not always accommodate the immediate needs of the user or service subscriber. A vehicle in long-term parking at an airport, for example, has been powered down for a while, but requires immediate telematics assistance when the owner returns to a vehicle with keys locked inside. When a vehicle is stolen, for example, a vehicle owner will want to retrieve vehicle location information quickly.
A method with a quicker response time is needed to make vehicle services available when the vehicle is powered down or turned off. This would result in increased subscriber satisfaction with telematics services. Increased availability and timeliness of services is compromised by the need to maintain low power consumption. The method would improve the availability of a vehicle to receive and perform a service request, while maintaining low power consumption.
It is an object of this invention, therefore, to provide a method for improving the availability of a quiescent vehicle to receive and perform a service request, and to overcome the deficiencies and obstacles described above.